The present invention relates to assemblies useful in inflatable restraint (air bag) systems and particularly relates to a retention device for supporting a gas generator retaining an air bag and for shielding the air bag from the heated gases produced by the gas generator.
Inflatable restraint systems are becoming the norm for passenger protection. A rudimentary system comprises of a crash sensor mounted to the vehicle frame and an air bag assembly positioned within the passenger compartment. Differing types of assemblies are used for driver side restraint systems and passenger side restraint systems. The present invention finds specific application with a passenger side air bag restraint system. These assemblies will often include an outer reaction can into which is received a gas generator. This can is a structurally sound member which absorbs and retransmits the air bag deployment forces to the vehicle. The can also supports the weight of the gas inflator and an air bag. Usually the air bag is placed into the can in close proximity to the gas generator and a cover is placed about the can to secure the bag in its nondeployed or stored condition. The reaction can is typically mounted to or near the dash board or instrument panel of the vehicle. Because the reaction can directly supports the weight of the gas generator and air bag and since it is used to transmit the deployment forces it weights is high adding to the overall vehicle weight.
The object of the present invention is to provide an integral air bag/gas inflator/heat shield member. A further object of the present invention is to form a one piece housing defining the retainer and heat shield that is subsequently formed into a cylindrical shape. Another object of the present invention is to provide means for securing a gas generator within the housing. Another object of the present invention is to provide such a device wherein the deployment reaction forces can be transmitted directly to the vehicle as opposed to a reaction can. An additional object is to use the retainer as a securement for the air bag and if the air bag includes tethers to secure the tethers to the retainer.
Accordingly, the invention comprises: a retainer for use in an air bag restraint system of the type using an air bag and gas generator. The retainer comprising a planar metal sheet having formed thereon at least a first set of opposing, generally U-shaped slots such that upon forming the sheet as an open ended cylinder the portions of the sheet, originally within the slots, extend away from the surface of the formed cylinder and form in conjunction with other surfaces of the metal sheet, a plurality of first apertures, and define heat shield means, such as wing-like projections, for shielding a portion of an air bag adapted to be secured thereabout from the hot gas generated, by a gas generator adapted to be secured therein. The invention includes securement means, interacting with a rearward portion of the formed cylinder to urge a gas generator into forward portions of the cylinder, proximate the apertures, thereby securing same in place. The securement means including a plurality of bolts threadably received within a holding member for guiding same into engagement with a Preferably deformable wall of the gas generator. As a result of the compressive engagement of the bolts to the wall, respective depressions are created such as by the elastic deformation of the wall in cooperation with each bolt, to assist in radially and axially securing the gas generator therein.
Many other objects and purposes of the invention will be clear from the following detailed description of the drawings.